Rack-Mounting Guidelines
The following sections provide guidelines for selecting racks and precautions for mounting the chassis on a
rack:
Precautions for Rack-Mounting
Follow these rack-mount guidelines to ensure your safety:
• Ensure that the rack is level and stable before extending a component from the rack.
• Ensure that proper airflow is provided to the components on the rack.
• Do not step on or stand on any component or system when servicing other systems or components on a
rack.
• If the rack is provided with stabilizing devices, install the stabilizers before mounting or servicing the
chassis.
Rack Selection Guidelines
Ensure the 2 or 4-post, 19 inches (48.3 centimeters) or 23 inches (58.42 centimeters) rack that you select
complies with the Electronic Industries Association (EIA) standard for equipment racks (EIA-310-D). The
rack must have at least two posts with mounting flanges to mount the chassis.
When mounting a chassis in any type of rack equipment, ensure that the temperature of the inlet air to the
chassis does not exceed the specified operating temperature of the chassis.
Caution
The distance between the center lines of the mounting holes on the two mounting posts must be 18.31 inches
(46.50 centimeters) ± 0.06 inch (± 0.15 centimeter). The rack-mounting hardware included with the chassis
is suitable for most 19 inches (48.3 centimeters) equipment racks.
Install the chassis on a rack with the following features:
• NEBS-compliant, 19 inches (48.3 centimeters) rack or 23 inches (58.42 centimeters).
• EIA or European Telecommunications Standards Institute (ETSI) hole patterns in the mounting rails.
The required mounting hardware is shipped with the chassis. If the rack on which you plan to install the
chassis has metric-threaded rails, you must provide your own metric-mounting hardware.
• Perforated top and open bottom for ventilation to prevent overheating.
• Leveling feet for stability.
Do not install the device on an enclosed rack because the chassis requires an unobstructed flow of cooling air
to maintain the acceptable operating temperature. If you use an enclosed rack, ensure that the airflow
requirements are maintained as discussed in the
section.
Receive the Device
Each device is shipped in a container that is strapped to a pallet.
Cisco ASR-920-12SZ-A and Cisco ASR-920-12SZ-D Aggregation Services Router Hardware Installation Guide
23
Prepare for Installation
Rack-Mounting Guidelines
